Motion
Do Now: Make a ramp with the yellow bin and the piece of wood. Race two objects down the ramp. Which object rolls faster? How can you tell?
SWBAT: explain when an object is in motion and how it is in motion relative to a reference point Vocabulary: Motion: an object is in motion when its distance from another object is changing
Do Now 1.How do you know an object is in motion? 2. Which is faster, a runner who moves 100 meters in 10 seconds, or a runner who moves 100 meters in 20 seconds? How do you know?
Reference point Sometimes it is not so easy to tell if something is moving – we are always moving
Relative Motion Am I moving? Compared to the tree? Compared to the windshield?
Reference point reference point: a reference point is a place or object used for comparison to determine if something is moving
Speed Speed = distance in one unit of time Speed = distance / time Speed does not have to be FAST!
Speed Time in sec Distance in m Do NOW; Using what you learned yesterday write 2 sentences about this graph.
Velocity velocity = the speed and the direction of an object’s movement
Velocity We use meters to measure distance mm: 1,000mm = 1 m _ Cm: 100 cm = 1m ______ Km: 1000 m = 1 km ___________________________________etc
Exit ticket Use the words speed, distance, and time. Tell me about the relationship of speed to distance if the time stays the same. As distance traveled increases, speed ____________. As speed increases, distance traveled ____________.
Velocity Calculate an object’s speed and velocity using SI units Velocity = distance / time in sec
Acceleration SWBAT describe what happens to the motion of an object as it accelerates, SWBAT define and identify acceleration
Acceleration Acceleration: rate of velocity change in either speed or direction. Acceleration can be increasing speed, decreasing speed or change of direction. Acceleration= (final v – initial v) / time
Acceleration – change in speed or direction
Acceleration? Yes or NO?
Do Now: Roll the marble to your elbow buddy. List 2 things you can change about the motion of a rolling marble.
Forces Force: a push or a pull Includes STRENGTH and DIRECTION
Net Forces Net force: overall force on an object after all forces are added together, If Net force is not zero it is unbalanced force An unbalanced force acting on an object will change an object’s motion
Balanced Forces BALANCED FORCES: equal forces acting in opposite directions A balanced force will not change an object’s direction
SWBAT: State Newton’s first law of motion, and define inertia Inertia: the tendency of an object to resist change in motion Newton’s first law of motion states that an object in motion will remain in motion and an object at rest will remain at rest unless acted upon by an unbalanced force
Newton’s Second Law of Motion Force depends on mass and acceleration Force = Mass x Acceleration F= M x A Force is measured in Newtons (N)
FORCE Force depends on both mass and acceleration Force is measured in Newtons Force = Mass x Acceleration F= M x A
DO NOW When you go sledding, what force makes you slide down the hill? What force stops you? Would you go as far if there wasn’t any snow on the hill? Why?
Friction and Gravity Friction and gravity are two forces that affect nearly all motion What determines the strength of the force of friction?
The type of the two surfaces The force which they are pressed together (how hard they rub) Heat is produced as a result of friction – some mechanical energy turns into thermal energy coming-home-from-space-space-shuttle- reentry-video.htm
The 2 persons are pushing each other on ice. (so no outside force). The grandma has twice the mass (inertia) than the little girl. Are they going to feel the same force ? according to what law ? Are they going to move as fast ? which one is going to move faster ?
Newton’s 3 rd law For every action, there is an equal and opposite reaction
Newton’s 3 rd Law of Motion For every action there is an EQUAL and OPPOSITE reaction
How does this show Newton’s 3 rd law